Pneumatic installation



Filed July 24, 194'? w n m m@ E m O WT n l L \|&A ma i s JB 1 l mn 2 51m) l Y \H\ ,M i

Patented Apr. 1, 1952 vUNITED STATES PATENT OFFICE 2,591,641 PNEUMATIC INSTALLATION Jean Troendl, Geneva, Switzerland Application July 24, 1947, Serial No. 763,273 In Switzerland May 10, 1947 2 Claims. l

The present invention relates to improvements in pneumatic installations comprising one cfr more sources of compressed air, one or more devices to be fed with compressed air, several compressedair reservoirs and conduits connecting the various elements just described to one another.

Such an installation may be used with great advantages on an aircraft for the pneumatic. remote control and actuation of various devices.

In an installation of the type described, the accidental breakage or failure of one of the compressed air reservoirs, or of the line connecting same to the installation, has the consequence that air will escape from the whole installation through the defective member, and, after a period of time depending on the seriousness of the failure the air pressure in the whole system will have dropped to a point where control can no longer be effected throughout the system.

The present invention has for its object an installation laid out in such a manner as to avoid the inconvenience noted above, in that first, on each conduit connecting the reservoirs to the compressed air source or sources, there is provided a safety device automatically shutting olf Y said conduit when the pressure of air contained in the corresponding reservoir has dropped below Y (not shown on the drawing) to be controlled or actuated by compressed air.

' its seat.

The pressure regulator 2 comprises a valve II enabling communication to be established between conduit I and another conduit I2 opening in the free atmosphere. Valve II is subjected to the action of a spring I3 tending to press it on In the opposite direction valve II is subjected to the actioncf the air pressure existing in the general supply line 4, the latter being connected to a' deformable chamber I4l with elastic walls. The free end of this deformable chamber actuates a rod I5 which can act on valve II. In addition, chamber I4 is subjected externally to the action of a spring I6 by the medium of a cap I'I and internally to the air pressure existing within. Adjusting spring I6 determines the maximum pressure to exist in the through duct I2 a predetermined value; second, on each conduit connecting the compressed air source or sources to each reservoir there is interposed a checkvalve forbidding air flow from the corresponding reservoir toward said compressed air source or sources; third, on each conduit connecting any reservoir to the devices to be supplied with compressed air there is interposed a check-valve forbidding air flow from said devices to be supplied with compressed air toward said reservoir.

The accompanying drawing shows diagrammatically and by way of example a form of embodiment of the invention.

The gure shows an installation in which an air compressor S takes air from the surrounding atmosphere, compresses it and forces it through conduit I, connected to a pressure regulator 2,

The safety devices 8, 8a and 8U are of the type of shut-off valves described in detail in my patent application No. 770,400, filed August 25, 1947. Each of them comprises a valve I8 interposed between conduits' 25 and 9. A spring I9 tends to maintain this valve on its seat which would result in shutting off the communication between these conduits. In the opposite direction the valve I8 is subjected to the action of a rod 20 sliding in a guide 2|. A connection exists between conduit 9 and chamber 22 in which a tact with the va1ve Is whue the other end cohtacts an inclined surface provided on the piston 23.

The piston, the valve and the springs are so dimensioned that when the pressure existing in and in turn connected by a check-valve 3 to a j general supply line 4. This line 4 feeds the valves 28, 28a and 28h. These control valves are actuated by control members 6, 6a and 6b for .v feeding through conduits 1, 1a and 1b the devices il? the conduit 9, and therefore in the chamber 22y is lower than a predetermined value, the piston 23 is moved toward the bottom of the chamber 22 (to the right on the figure) under the action of the spring 24. The slope of the inclined surface of the piston 23 in contact with the rod 20 is such that during the motion of the piston, the valve I 8 becomes free and is actuated by its spring I9.

It may be seen from the drawing that if conduit 4 is accidentally damaged, check-valves 26, 26a and 26h prevent the loss of compressed air contained in the reservoirs I0, Illa and IIIb.

On the other hand, if one or more reservoirs or their individual connection 9, 9ct or 5b is damaged and leaks, as soon as the pressure in the corresponding connection has dropped below a predetermined value due to such a failure, the corresponding valve 8, 8a or 8b closes automatically and prevents air contained in the system, that is, air coming either from general supply line 4 or from other intact reservoirs, from escaping into the atmosphere and thereby keeps the installation in service. For putting a new loaded reservoir in operation it is suicient to screw it in place with its hand-operated valve V, Va, or Vb` closed. Then, opening said valve will allow air from the reservoir to create in space 22 a pressure suicient to actuate piston 23 toward the left, which will cause valve i8 to open.

In practice, in order to minimize the risks of leakage, safety valves 8, 8d and 8b, check valves 26, 26a and 2Gb, 28, 28a and 28h as Well as control valves 5, a and 5b will be grouped in one single block unit thus avoiding numerous connecting pipes, couplings and ittings.

I claim:

l. In a pneumatic installation the combination comprising at least one source of compressed air, a supply line connected to the source, a plurality of branch conduits connected at one end to the` supply line, a check Valve in each of the branch conduits, an equal plurality of pairs of second branch conduits, each pair of second branch conduits being connected at one end to one of said first branch conduits, a plurality of reservoirs each connected to the other end of one of a pair of second branch conduits, a plurality of valves each controlling the connection of a second branch conduit to a reservoir and closed by the pressure in the reservoir dropping below a predetermined value, a plurality of second check valves one in the other one of each pair of second branch conduits, and a utilization manifold connected to the other ends of the other ones of the pairs of second branch conduits, and Valve means connected to the other ends of the other second branch conduits and operable to supply air therefrom.

2. The combination according to claim 1 and also comprising a pressure regulator in the supply line.

JEAN TROENDL.

REFERENCES CITED The following references are of record in the file of this patent:

UITED STATES PATENTS Number Name Date 735,544 Mann Aug. 4, 1903 1,471,800 Nalley Oct. 23, 1923 2,294,396 Feuchter Sept. 1, 1942 2,294,397 Feuchter Sept. 1, 1942 2,306,382 Fink Dec. 29, 1942 2,345,475 Herman Mar. 28, 1944 

